Well, this is unsettling. According to this year's data, not a single female student, black student, or Latino student took the AP computer science exam in either Montana or Mississippi. That means it was pretty much just all white dudes. Not exactly a heartening indicator of all that "diversity in tech" that tech professionals are supposedlysocommittedto.

There are 11 states where not a single African-American took the test, and eight states where no Hispanics sat for the exam.

We're not talking here about people who passed or didn't pass, either. We're talking about people who simply took the test, which means African-Americans, Hispanics and girls aren't enrolling in AP computer science classes in the first place.

Of the approximately 30,000 students who took the exam in 2013, only around 20 percent were female, according to the analysis, and a tiny 3 percent were African-American. Just 8 percent were Hispanic.

One reason there are so few students enrolling in the class and taking the test is that AP computer science courses are more common in suburban and private schools, Barbara Ericson, a senior research scientist with Georgia Tech who compiled the data, told the blog Education Week, and those schools tend to be less diverse than urban and public schools.

Another potential reason is that there are so few women, African-American and Hispanic instructors teaching computer science and so few working in the computer science field. Students are more likely to pursue a course of study if they have mentors with similar backgrounds to emulate.

Obviously Silicon Valley doesn't have the power to reach over into rural Mississippi and drag girls and people of color into the exam room to take tests on subjects that their underserved schools don't even offer. But that doesn't mean that the tech world at large isn't at least partially responsible for what types of people see themselves growing up and working in that industry. When girls only get to see themselves as "booth babes" or harridan killjoys, and black kids hardly get to see themselves anywhere at all, what initiative do you expect them to take to fix your industry? Representation problems are self-perpetuating, and they're not the fault of teenagers.